Direct measurement of gas transmission rates of coated commodity under controlled environmental conditions is needed in formulating coatings to extend shelf life of fruits. The gas transmission rate of coated commodities, along with its respiration rate can be used to predict the level of modification of internal atmosphere and the quality of the product during storage. Oxygen (O2) and carbon dioxide (CO2) transmission rates of mango (Mangifera indica L. cv Carabao) peel coated with different formulations of chitosan-nanosilica at three storage temperatures were estimated using Exponential Decay Method. The coating was prepared by dissolving chitosan (CS) in aqueous solution of glacial acetic acid (0.25% v/v) and blending with nanosilica (NS) dispersion. The resulting films have microcracks and agglomeration of NS throughout the surface. 0.75% CS at 25°C had the highest gas transmission rate (1.136 mLO2 cm-2 h -1 and 3.243 mLCO2 cm-2 h -1 ) whereas 1% CS+ 0.03% NS at 15°C had the lowest gas transmission rate (0.406 mLO2 cm-2 h -1 and 1.586 mLCO2 cm-2 h -1 ). At constant temperature, increasing chitosan concentration decreases O2 and CO2 transmission rates by almost 44% and 41%, respectively, whereas the incorporation of NS decreases the O2 transmission rate by 10% to 20% and CO2 transmission rate by 5% to 14%. Gas transmission rates were highest at 25°C and lowest at 15°C